Transient suppression of hepatocellular replication in the mouse liver following transduction with recombinant adeno-associated virus.

Recombinant vectors based on adeno-associated virus (AAV) are proving to be powerful tools for genetic manipulation of the liver, for both discovery and therapeutic purposes. The system can be used to deliver transgene cassettes for expression or, alternatively, DNA templates for genome editing via homologous recombination. The replicative state of target cells is known to influence the efficiency of these processes and knowledge of the host-vector interactions involved is required for optimally effective vector deployment. Here we show, for the first time in vivo, that in addition to the known effects of hepatocellular replication on AAV-mediated gene transfer, the vector itself exerts a potent, albeit transient suppressive effect on cell cycle progression that is relieved on a time course that correlates with the known rate of clearance of input single-stranded vector DNA. This finding requires further mechanistic investigation, delineates an excellent model system for such studies and further deepens our insight into the complexity of interactions between AAV vectors and the cell cycle in a clinically promising target tissue.